Abstract
Background & Objective
Current guidelines reccommend post-bronchodilator spirometry to confirm a diagnosis of COPD. We investigated whether a self-reported diagnosis of COPD was associated with prior spirometry and, whether a correct diagnosis of COPD was more likely when spirometry was reported.
Methods
We used data from the population-based Austrian BOLD study. Participants were aged >40 years, and completed the BOLD questionnaire and post-bronchodilator spirometry.
Reported COPD diagnosis and reported prior lung function test were based on questionnaire. Non-reversible airways obstruction (AO) was defined as post-bronchodilator FEV1/FVC <0.7.
A correct diagnosis of COPD was defined, when subjects reported a prior COPD diagnosis and demonstrated non-reversible airways obstruction on post-bronchodilator spirometry.
Results
68 (5.4%) of 1258 participants reported a prior physician's diagnosis of COPD. Among those only 25.0% (17/68) reported a lung function test within the past 12 months, and 67.6% (46/68) at any time in the past. The likelihood for a correct COPD GOLD stage I+ diagnosis was similar among subjects reporting (likelihood ratio 2.07 [95% CI; 0.89 – 5.50 C.I.]) and subjects not reporting (likelihood ratio 2.78 [95% CI; 1.58 – 4.87]) a lung function during the last 12 months. Similar likelihood ratios were seen when GOLD stage II+ was investigated and, when lung function was reported at any time in the past.
Conclusion
One third of subjects with a reported diagnosis of COPD never had a lung function test. When spirometry was reported, this did not increase the likelihood for a correct COPD diagnosis.
- © 2012 ERS
